Well packer



C. C. BROWN April s, 1958 WELL PACKER 3 Sheets-Sheet 1 Filed NOV. 2, 1953 C/cerb C. BI/OWN INVENTOR.

A Tram/5 y c. c. BROWN WELL PACKER A ril s, 1958 3 Sheets-Sheet 2 Filed Nov. 2, 1953 C/cer'o C. Brown INVENTOR.

ATTOR/VEV April 8 c. c. BROWN 2,829,717

- WELL PACKER Filed. Nov. 2, 1953 5 Sheets-Sheet 3 W 7. 2B W 4d 'C/cero C. 5/0 vvn INVENTOR.

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A T TOR/V5 Y ited States This invention relates to well packers.

It is a primary object of the present invention to provide an improved form of well packer wherein the operating stem employed for setting and releasing the packer may, alter the packer has been set, be moved longitudinally or rotationally within the packer, as may be required to perform any number of operations in the well, and particularly below the packer- A further object of this invention is to provide a packer employing wall-gripping slips which are set or released by positive mechanical means, and a sealing element actuated by fluid pressures existing in the well to seal the well bore.

In the operation of deep wells, such as oil and gas wells, it is often necessary to conduct various operations, such as gravel packing, cementing, acidizing, and the like, wherein it is ordinarily necessary to set a packer in the well bore in order to seal off the portion of the bore in which the work is to be conducted from the remainder of the bore. in such operations, it is usually desirable to be able to operate tools below the packer. More conventional types of packers are so constructed that various restrictions are left in the bore of the packer such that it is impractical, if not impossible, to operate a string of tools through the packer, without disturbance of the packer.

In accordance with the present invention, a packer structure is provided through which, after the packer has been set, a string of tools may be operated without difliculty by merely attaching them to, or making them a part of, the operating stem which is employed to set the packer and which is connected to a string of pipe leading to the surface, the stem being first employed to set the packer and thereafter employed as a part of the working string.

"arious other objects and advantages of this invention will become more readily apparent from the following detailed description when read in conjunction with the accompanying drawing, which illustrates several useful embodiments in accordance with this invention.

In the drawing,

Fig. 1 is a largely diagrammatic view showing a packer structure in accordance with one embodiment of this invention positioned in a well bore, the parts of the packer being shown in the set position;

Figs. 2, 2A, 2B and 2C, taken together, constitute a longitudinal View, partly in section, of a packer structure in accordance with the present invention, the parts of the structure being shown in the inactive or unset position;

Fig. 3 is a cross-sectional View taken along line 3-3 of Fig. 2;

Fig. 4 is a fragmentary longitudinal view, partly in section, of the packer structure employing a modified form of a sealing element.

As best seen in Figs. 2 to 2C, inclusive, the packer structure comprises a tubular body 5 on which is mounted a slip assembly, designated generally by the numeral 6,

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1 2 and a sealing assembly, designated generally by the numeral 7.

Slip assembly 6 comprises a tubular slip cage 8 which surrounds body 5 and which is provided with a plurality of angularly spaced, generally rectangular, windows 9, in which are mounted a corresponding number of segmental slips 10 arranged in the windows for radial move ment therein. Each of the slips 10 is provided externally with a toothed or serrated face 11 and internally with a downwardly and outwardly tapering face 12.. Body 5 has a thread section 13 positioned on its exterior substantially opposite slips 10. A tubular mandrel 14 is mounted inside the lower end of cage 8 between the cage and the exterior of body 5. At its upper end, mandrel 14 has internal threads 15 adapted to engage threads 13 on the body. The outer surface of mandrel 14, at its upper end, is tapered inwardly to form the conical surface 16 which is adapted to engage surfaces 12 of the slips. The lower end of the mandrel is secured to the lower portion of cage 8 by means of a plurality of angularly spaced pins 17 which extend radially through the wall of the mandrel and have heads 18 which project outwardly from the mandrel and are received in elongated slots 19 provided in the wall of cage 8 to thereby permit relative axial movement between the mandrel and the cage, while preventing relative rotation between these members. The upper end of cage 8 is closed by a screw cap 19a having an internal shoulder 20 near its upper end. The upper end of cage 8 is counterbored at 21 to receive an annular shoulder 22 secured to the exterior of body 5. An anti-friction bearing 23 is mounted inside cap 1% between shoulder 20 and the upper end of cage 8 and shoulder 22, whereby body 5 may rotate freely relative to cage 8, while the cage remains supported on shoulder 22. Secured to the upper end of body 5, as by means of threads 24a and a set screw 24b, is a tubular extension 24 having one or more J-slots 25 therein, the open legs 26 of which open to the upper end of extension 24 (Fig. 2).

The construction of the slip assembly, as above described, is such that it will be seen that when body 5 is rotated in one direction, the engagement of threads 13 and 15 will cause mandrel 14 to move upwardly relative to cage 8 and cause the tapering surface 16 of the mandrel to engage surfaces 12 of the slips and thereby urge the slips outwardly. Rotation of the body in the opposite direction will cause the mandrel to retract and allow the slips to move inwardly. Cage 8 has mounted on the exterior thereof a plurality of drag springs 62 which are adapted to resiliently engage the well wall to hold the cage stationary in order to permit rotation of body 5 relative thereto.

As best seen in Fig. 2B, sealing assembly 7 comprises upper and lower metallic collars 27 and 28, respectively, which are spaced apart longitudinally along body 5. A generally tubular sealing sleeve 29 is mounted about body 5 between collars 27 and 28, the opposite ends of the sleeve being secured to hinge rings 30-30 having outwardly turned lips 31-31 which engage with inwardly turned lips 32-32 carried by the inner ends of collars 27 and 28, this structure providing means for a small amount of pivoting movement between the hinge rings and the ends of the collars. The interior of sealing sleeve 29 is formed to have an annular chamber 33, the outer wall of which is defined by the inner wall of sleeve 29 and the inner wall of the chamber being defined by the exterior of body 5. Sealing lips 34-34 are formed in the bore of the sealing sleeve at the opposite ends of chamber 33 to engage the exterior of body 5 in order to seal therewith. One or more ports 35 are provided in the wall of body 5 between the ends of chamber 33.

A pair of metal reinforcing rings 36-36 may be molded into the exterior surface of sleeve 2% adjacent hinge rings 30. The section of sleeve 29 extending between the reinforcing rings is molded or formed to provide an outwardly enlarged section 37. The unstressed external diameter of section 37 is made such with relation to the interior diameter of the well wall that the exterior surface of section 37 will normally be in frictional engagement with the well wall (see Fig. 1). The term ell wall, as used herein, refers either to the bore wall of the well or to the inner wall of a casing lining the well bore. A tubular cap 38 is secured to upper collar 27 and has its upper end extending radially inwardly about the exterior of body 5, the latter being provided with an annular ledge or shoulder 39 which is received within cap 33 below its upper end. An antifriction bearing 4% is mounted bctween shoulder 29 and the upper end of collar 27 to thereby provide a freely rotatable connection between body and sea-ling assembly 7. The lower collar 28 is provided with a screw cap 41 having an inwardly turned lip 42 spaced from the lower end of collar 28. A tubular extension 43 is mounted on the lower end of body 5 and extends into cap 41. The inner end of extension 43 is provided with an external, downwardly facing shoulder 44 adapted to abut against lip 42. A11 antifriction bearing 45 is mounted between the upper end of extension and the lower end of collar 2%. A plurality of angularly spaced radial ports 46 are provided through the wall of extension 43 at a point somewhat below cap 41 to provide communication between the interior and exterior of body 5. Extension 43 is provided with one or more J-slots 47 each having one leg opening to the lower end of the extension, J-slots 47 being substantially identical in form with upper J-slots 25.

A tubular operating stem 48 extends entirely through body 5 and carries on its upper end radially projecting J-lugs 49 mounted on a collar 50 secured to the upper end of stem 48 and having an internally threaded socket 51 for connecting the operating stem to a string of pipe 52 which extends to the surface of the well. At its lower end, operating stem 48 carries a second set of radially projecting J-lugs 53 mounted on a collar 54 which is secured to the lower end of stem 48 and is provided with internally threaded socket 55 for connection to the stem of additional pipe joints or other tools 56. The length of stem 48 between lugs 49 and 53 is made greater than the distance between J-slots 25 and 47 so that only one set of the J-lugs may be received in one of the J-slots at one time, the other J-lug being disengaged from its J-slot. This length between the J-lugs may be as great as desired, so that when the lower J-connection has been disengaged the operating stem may be reciprocated through the bore of the. device through any distance desired, as will be more fully explained hereinafter.

Operating stem 4-8 is provided with a plurality of ports 57 preferably at a point which will be substantially opposite the upper end of extension 24 when the lower J-connection is engaged. Extension 24 is provided with an internal annular shoulder 58 which extends inwardly thereof to a point closely adjacent the exterior of stem 48, the external diameter of the stem being made somewhat smaller than the external diameter of body 5 to de fine the annular space 59 (Fig. 2B) therebetween. The upper end of body 5 extends into the lower end of extension 24 to a point somewhat below shoulder 58, thereby providing a stufling box 60 in which a packing 61 is installed and compressed between shoulder 53 and the upper end of body 5 to provide a fluid-tight seal between stem 48 and body 5 which will, at the same time, permit longitudinal and rotational movement of the stern relative to the body.

The device is operated in the following manner: The structure is assembled in the manner shown in Figs. 2 to 2C, inclusive, that is, with J-lugs 53 locked in J-slots 4'7 and will be inserted into the well bore. It will be seen that with the lower J-lugs locked in J-slots 47, ports 57 will be above packing 61 and as the device is lowered into the well, fluid in the well will be displaced through the interior of stem 43 and outwardly through ports 57 into the annular space between the exterior of the device and the well wall, thereby allowing the device to be lowered into a well filled with fluid without interference by the fluid. It will be understood that in the inactive position of the device, mandrel 14 will be in the retracted position illustrated in Fig. 2A, and slips 10 will be likewise in their retracted position. Enlarged section 37 of the sealing sleeve and drag springs 62 will be in frictional engagement with the wall of the well but the resistance to downward movement of the device exerted by this frictional engagement will be readily overcome by the weight of the device as it is lowered in the well.

When the device has been inserted in a well 63 (Fig. 1) to the desired depth, body 5 will be rotated in a direction, acting through the engagement of threads 13 and 15, to advance mandrel 14 into expansive engagement with slips 10. The rotation of body 5 will be effected by rotating tubing string 52, which will act through stem 48 and its connection with extension 43 formed by the engagement of lugs 53 in J-slots 47 to rotate body 5. Since cage 8 will be held against rotation by the engagement of drag springs 62 with the well wall, mandrel 14 will be constrained by its threaded engagement with body 5 to move upwardly relative to cage 8 and to urge slips 10 outwardly into gripping engagement with the well wall. Since enlarged section 37 of the sealing sleeve will also be in frictional engagement with the well wall, body 5 will turn freely relative to the sealing assembly while the slips are being set as described.

When the slips have been firmly set in the well wall, the packer structure will thus be anchored to the well wall. Thereupon stem 4% will be manipulated by appropriate manipulation of the operating pipe 52 to un lock the lower J-connection by placing lugs 53 in registration with the open leg of J-slot 47. Thereupon, the operating stem will be lowered through body 5 until ports 57 are below packing 61. This will serve to cut off communication between the interior of the operating stern and the portion of the well bore above the packer. With this communication thus cut off, any pressure present or developed in the well below the packer will be communicated to the interior of chamber 33 inside sealing sleeve 29 by passage through ports 46, annular space 59 and ports 35, and will act to urge section 37 of the sealing sleeve outwardly and into increasingly tight engagement with the well wall. The pressure employed to thus expand sleeve 29 may be that already existent in the well below the packer or may be created by forcing fluid through the operating string and stem 43 into the lower portion of the well bore. The greater the pressure differential across the packer the tighter will be the seal formed by sealing sleeve 29 with the well wall.

With the well thus sealed off, stem 48 may then be reciprocated or rotated in body 5 to the full extent of the length of the stem in order perform various operations in the well or to manipulate tools connected thereto below the packer, as may be desired. The seal formed by sleeve 29 will be maintained so long as ports 57 remain below packing 61, since annular space 59 will continue to maintain communication between ports 46 and 35. Fig. 1 illustrates the packer in set position with the lower J-connection disconnected and the stem projected well below the packer.

When it is desired to remove the packer, stem 48 will be drawn upwardly to raise ports 57 above packing 61 whereby the pressures above and below the packer may again be equalized through ports 57, thereby relieving the internal pressure on sleeve 29. J-lugs 53 will again be locked in J-slot 47 and stem 48 rotated in a direction to cause mandrel 14 to be retracted from engagement with slips 19 which will thus be freed to move inwardly of cage 8. An upward pull applied to the operating stem will then draw the packer from the well.

Fig. 4 illustrates a modification of the above-described device, differing therefrom primarily in substituting for the chambered sealing sleeve 29, a flexible sealing cup 65 which opens downwardly, being provided with a downwardly and outwardly flaring annular skirt 66, the external molded diameter of which is such as to normally frictionally engage the well wall. in all other major respects the parts of the modified device are substantially identical with those of the previously described embodiment.

With this modified construction of Fig. 4, it will be seen that when stem it?- is lowered to move ports 57 below the seal formed by packing all, the unbalanced pressure created below sealing cup as will be exerted against the interior of skirt as and urge it more tightly against the well wall and thus maintain a tight seal be tween body 5 and the well wall, stem 48 being thus freed for manipulation to function in the same manner as the previously described embodiment.

The upper J-connection comprising .l-slots 255 and J- lugs 49, while useful, may not be necessary in many cases. It is provided, however, for those instances in which it may be desirable to run the tool into the Well with oper ating stem 48 initially in its lowermost position relative to body 5. It will be evident that the upper J-connection may be employed in the same manner as the lower 1- connection for setting and releasing the packer.

It will be understood that numerous alterations and modifications may be made in the details of the illustrative embodiments within the scope of the appended claims but without departing from the spirit of this invention.

What I claim and desire to secure by Letters Patent is:

l. A well packer, comprising, a tubular body insertible in a well, a slip cage rotatably mounted on said body, means carried by the slip cage for engaging the well wall to restrain rotation of the cage, radially movable slips mounted in said cage, mandrel means positioned between the body and the slips, a non-rotative siidable connection between the mandrel means and the cage, said mandrel means having threaded connection to said body whereby rotation of the body relative to the mandrel means will move the mandrel means into and out of wedging engagement with the slips, an annular resilient packer element rotatably mounted on the body and having a normal unstressed external diameter to maintain engagement with the wall of said well, a tubular operating stem slidably extending through said body, an annular seal between the stem and body above the packer element, ports in said stem movable therewith from a position above said seal to a position below said seal to respectively open and close communication between the portions of the well above and below the packer element, and means for rcleasa-bly locking the stem to the body.

2. A well packer, comprising, a tubular body insertible in a well, a slip cage rotatably mounted on said body, means carried by the slip cage for engaging the well wall to restrain rotation of the cage, radially movable slips mounted in said cage, mandrel means: positioned between the body and the slips, a non-rotative slidable connection between the mandrel means and. the cage, said mandrel means having threaded connection to said body whereby rotation of the body relative to the mandrel means will move the mandrel means into and out of wedging engagement with the slips, an annular resilient packer element rotatably mounted on said body, said packer element comprising a generally tubular sleeve having a normal unstressed external diameter to maintain continuous engagement with the wall of said well, an opening in said body communicating with the interior of said sleeve, a tubular operating stem slidably extending through said body, an annular seal between the stem and body above said opening, ports in said stem movable therewith between positions above and below said seal to respectively open and close communication between the portions of the well above and below the packer element, and means for releasably connecting the stem to the body.

3. A Well packer, comprising, a tubular body insertible in a well, a slip cage rotatably mounted on said body, means carried by the slip cage for engaging the well Wall to restrain rotation of the cage, radially movable slips mounted in said cage, mandrel means positioned between the body and the slips, a non-rotative slidable connection between the mandrel means and the cage, said mandrel means having threaded connection to said body whereby rotation of the body relative to the mandrel means will move the mandrel means into and out of wedging engagement with the slips, an annular resilient packer element rotatably mounted on said body, said packer element being of downwardly open cup-shape and having a normal unstressed external diameter to maintain continuous engagement with the wall of said well, a tubular operating stern slidably extending through said body, an annular seal between the stem and body above said packer element, ports in said stem movable therewith between positions above and below said seal to respectively open and close communication between the portions of the well above and below the packer element, and means for releasably connecting the stem to the body.

References Cited in the file of this patent UNITED STATES PATENTS 2,374,169 Boynton Apr. 24, 1945 2,384,192 Otis et a1 Sept. 4, 1945 2,715,442 Brown Aug. 16, 1955 

